Solubility of oxygen, carbon dioxide and water in semifluorinated alkanes and in perfluorooctylbromide by molecular simulation

Solubilities of oxygen, carbon dioxide and water in substituted fluorocarbons perfluoroctylethane (PFOE), perfluorohexylethane (PFHE), perfluorohexylhexane (PFHH) and perfluoroalkylbromide (PFOB) were studied by computer simulation, between 293 and 313 K at 1 bar. The solubilities do not show a marked temperature dependence, are similar in all solvents and have values of the order of 4×10⁻³ for oxygen, 2×10⁻² for carbon dioxide and 3×10⁻⁶ for water, in mole fraction. The gases are slightly less soluble in PFHE when compared with the other solvents, whereas water is slightly more soluble in this liquid. The solubilities were obtained from Henry’s law coefficients, in turn derived from residual chemical potentials of the solutes at infinite dilution obtained by molecular simulation techniques using full atomistic force fields.